Cancer is the leading cause of death from disease in American children over age 1 year. Recent improvements in diagnosis, evaluation and treatment are resulting in improved survival for children with Wilm's tumor, acute lymphocytic leukemia, lymphoma, and bone and soft tissue tumors, who receive optimal management. However, etiology and mechanisms are still unknown, treatment is only partly effective and often hazardous, and there are serious deficiencies in utilization of the current knowledge and techniques available for prevention, diagnosis and therapy. The purpose of this center is to reduce morbidity and mortality of childhood cancer through clinical research, education and improved methods of diagnosis, evaluation and treatment. It (1) serves as a pediatric component of the Wisconsin Clinical Cancer Center (WCCC), (2) collaborates with basic cancer research and clinical units of the WCCC, (3) determines pharmacokinetics and efficacy of new anti-cancer drugs in children and optimal methods of using them, (4) develops further knowledge of the immune system in children with cancer and possible ways of utilizing it for understanding and treating cancer, (5) explores innovative methods of treating childhood cancer, (6) assesses more completely the infectious problems peculiar to immunosuppressed children and develops ways to prevent or control them and (7) develops cancer educational programs for physicians, basic scientists, medical students and nurses. The physical facilities consist of approximately 10,000 square feet of new research laboratories, an 8 bed specialized chemotherapy inpatient unit, and an 8 room outpatient clinic, all located at Milwaukee Children's Hospital.